[PATCH v2 3/4] drm: rcar-du: fix DSI enable & disable sequence
Laurent Pinchart
laurent.pinchart at ideasonboard.com
Mon Aug 22 13:40:46 UTC 2022
Hi Tomi,
Thank you for the patch.
On Mon, Aug 22, 2022 at 04:05:11PM +0300, Tomi Valkeinen wrote:
> From: Tomi Valkeinen <tomi.valkeinen+renesas at ideasonboard.com>
>
> The rcar crtc depends on the clock provided from the rcar DSI bridge.
> When the DSI bridge is disabled, the clock is stopped, which causes the
> crtc disable to timeout.
>
> Also, while I have no issue with the enable, the documentation suggests
> to enable the DSI before the crtc so that the crtc has its clock enabled
> at enable time. This is also not done by the current driver.
>
> To fix this, we need to keep the DSI bridge enabled until the crtc has
> disabled itself, and enable the DSI bridge before crtc enables itself.
>
> Add functions (rcar_mipi_dsi_atomic_early_enable and
> rcar_mipi_dsi_atomic_late_disable) to the rcar DSI bridge driver which
The function names don't match the code. With this fixed,
Reviewed-by: Laurent Pinchart <laurent.pinchart at ideasonboard.com>
> the rcar driver can use to enable/disable the DSI clock when needed.
> This is similar to what is already done with the rcar LVDS bridge.
>
> Signed-off-by: Tomi Valkeinen <tomi.valkeinen+renesas at ideasonboard.com>
> ---
> drivers/gpu/drm/rcar-du/rcar_du_crtc.c | 26 +++++++++++++++++++
> drivers/gpu/drm/rcar-du/rcar_du_drv.h | 2 ++
> drivers/gpu/drm/rcar-du/rcar_du_encoder.c | 4 +++
> drivers/gpu/drm/rcar-du/rcar_mipi_dsi.c | 25 +++++++++++++-----
> drivers/gpu/drm/rcar-du/rcar_mipi_dsi.h | 31 +++++++++++++++++++++++
> 5 files changed, 82 insertions(+), 6 deletions(-)
> create mode 100644 drivers/gpu/drm/rcar-du/rcar_mipi_dsi.h
>
> diff --git a/drivers/gpu/drm/rcar-du/rcar_du_crtc.c b/drivers/gpu/drm/rcar-du/rcar_du_crtc.c
> index fd3b94649a01..31e33270e6db 100644
> --- a/drivers/gpu/drm/rcar-du/rcar_du_crtc.c
> +++ b/drivers/gpu/drm/rcar-du/rcar_du_crtc.c
> @@ -29,6 +29,7 @@
> #include "rcar_du_regs.h"
> #include "rcar_du_vsp.h"
> #include "rcar_lvds.h"
> +#include "rcar_mipi_dsi.h"
>
> static u32 rcar_du_crtc_read(struct rcar_du_crtc *rcrtc, u32 reg)
> {
> @@ -747,6 +748,18 @@ static void rcar_du_crtc_atomic_enable(struct drm_crtc *crtc,
> rcar_lvds_clk_enable(bridge, mode->clock * 1000);
> }
>
> + /*
> + * Similarly to LVDS, on V3U the dot clock is provided by the DSI
> + * encoder, and we need to enable the DSI clocks before enabling the CRTC.
> + */
> + if ((rcdu->info->dsi_clk_mask & BIT(rcrtc->index)) &&
> + (rstate->outputs &
> + (BIT(RCAR_DU_OUTPUT_DSI0) | BIT(RCAR_DU_OUTPUT_DSI1)))) {
> + struct drm_bridge *bridge = rcdu->dsi[rcrtc->index];
> +
> + rcar_mipi_dsi_pclk_enable(bridge, state);
> + }
> +
> rcar_du_crtc_start(rcrtc);
>
> /*
> @@ -780,6 +793,19 @@ static void rcar_du_crtc_atomic_disable(struct drm_crtc *crtc,
> rcar_lvds_clk_disable(bridge);
> }
>
> + if ((rcdu->info->dsi_clk_mask & BIT(rcrtc->index)) &&
> + (rstate->outputs &
> + (BIT(RCAR_DU_OUTPUT_DSI0) | BIT(RCAR_DU_OUTPUT_DSI1)))) {
> + struct drm_bridge *bridge = rcdu->dsi[rcrtc->index];
> +
> + /*
> + * Disable the DSI clock output, see
> + * rcar_du_crtc_atomic_enable().
> + */
> +
> + rcar_mipi_dsi_pclk_disable(bridge);
> + }
> +
> spin_lock_irq(&crtc->dev->event_lock);
> if (crtc->state->event) {
> drm_crtc_send_vblank_event(crtc, crtc->state->event);
> diff --git a/drivers/gpu/drm/rcar-du/rcar_du_drv.h b/drivers/gpu/drm/rcar-du/rcar_du_drv.h
> index bfad7775d9a1..9367c2f59431 100644
> --- a/drivers/gpu/drm/rcar-du/rcar_du_drv.h
> +++ b/drivers/gpu/drm/rcar-du/rcar_du_drv.h
> @@ -91,6 +91,7 @@ struct rcar_du_device_info {
> #define RCAR_DU_MAX_GROUPS DIV_ROUND_UP(RCAR_DU_MAX_CRTCS, 2)
> #define RCAR_DU_MAX_VSPS 4
> #define RCAR_DU_MAX_LVDS 2
> +#define RCAR_DU_MAX_DSI 2
>
> struct rcar_du_device {
> struct device *dev;
> @@ -107,6 +108,7 @@ struct rcar_du_device {
> struct platform_device *cmms[RCAR_DU_MAX_CRTCS];
> struct rcar_du_vsp vsps[RCAR_DU_MAX_VSPS];
> struct drm_bridge *lvds[RCAR_DU_MAX_LVDS];
> + struct drm_bridge *dsi[RCAR_DU_MAX_DSI];
>
> struct {
> struct drm_property *colorkey;
> diff --git a/drivers/gpu/drm/rcar-du/rcar_du_encoder.c b/drivers/gpu/drm/rcar-du/rcar_du_encoder.c
> index 60d6be78323b..ac93e08e8af4 100644
> --- a/drivers/gpu/drm/rcar-du/rcar_du_encoder.c
> +++ b/drivers/gpu/drm/rcar-du/rcar_du_encoder.c
> @@ -84,6 +84,10 @@ int rcar_du_encoder_init(struct rcar_du_device *rcdu,
> if (output == RCAR_DU_OUTPUT_LVDS0 ||
> output == RCAR_DU_OUTPUT_LVDS1)
> rcdu->lvds[output - RCAR_DU_OUTPUT_LVDS0] = bridge;
> +
> + if (output == RCAR_DU_OUTPUT_DSI0 ||
> + output == RCAR_DU_OUTPUT_DSI1)
> + rcdu->dsi[output - RCAR_DU_OUTPUT_DSI0] = bridge;
> }
>
> /*
> diff --git a/drivers/gpu/drm/rcar-du/rcar_mipi_dsi.c b/drivers/gpu/drm/rcar-du/rcar_mipi_dsi.c
> index 6a10a35f1122..b8fabf821a12 100644
> --- a/drivers/gpu/drm/rcar-du/rcar_mipi_dsi.c
> +++ b/drivers/gpu/drm/rcar-du/rcar_mipi_dsi.c
> @@ -598,7 +598,22 @@ static int rcar_mipi_dsi_attach(struct drm_bridge *bridge,
> static void rcar_mipi_dsi_atomic_enable(struct drm_bridge *bridge,
> struct drm_bridge_state *old_bridge_state)
> {
> - struct drm_atomic_state *state = old_bridge_state->base.state;
> + struct rcar_mipi_dsi *dsi = bridge_to_rcar_mipi_dsi(bridge);
> +
> + rcar_mipi_dsi_start_video(dsi);
> +}
> +
> +static void rcar_mipi_dsi_atomic_disable(struct drm_bridge *bridge,
> + struct drm_bridge_state *old_bridge_state)
> +{
> + struct rcar_mipi_dsi *dsi = bridge_to_rcar_mipi_dsi(bridge);
> +
> + rcar_mipi_dsi_stop_video(dsi);
> +}
> +
> +void rcar_mipi_dsi_pclk_enable(struct drm_bridge *bridge,
> + struct drm_atomic_state *state)
> +{
> struct rcar_mipi_dsi *dsi = bridge_to_rcar_mipi_dsi(bridge);
> const struct drm_display_mode *mode;
> struct drm_connector *connector;
> @@ -626,8 +641,6 @@ static void rcar_mipi_dsi_atomic_enable(struct drm_bridge *bridge,
> if (ret < 0)
> goto err_dsi_start_hs;
>
> - rcar_mipi_dsi_start_video(dsi);
> -
> return;
>
> err_dsi_start_hs:
> @@ -635,16 +648,16 @@ static void rcar_mipi_dsi_atomic_enable(struct drm_bridge *bridge,
> err_dsi_startup:
> rcar_mipi_dsi_clk_disable(dsi);
> }
> +EXPORT_SYMBOL_GPL(rcar_mipi_dsi_pclk_enable);
>
> -static void rcar_mipi_dsi_atomic_disable(struct drm_bridge *bridge,
> - struct drm_bridge_state *old_bridge_state)
> +void rcar_mipi_dsi_pclk_disable(struct drm_bridge *bridge)
> {
> struct rcar_mipi_dsi *dsi = bridge_to_rcar_mipi_dsi(bridge);
>
> - rcar_mipi_dsi_stop_video(dsi);
> rcar_mipi_dsi_shutdown(dsi);
> rcar_mipi_dsi_clk_disable(dsi);
> }
> +EXPORT_SYMBOL_GPL(rcar_mipi_dsi_pclk_disable);
>
> static enum drm_mode_status
> rcar_mipi_dsi_bridge_mode_valid(struct drm_bridge *bridge,
> diff --git a/drivers/gpu/drm/rcar-du/rcar_mipi_dsi.h b/drivers/gpu/drm/rcar-du/rcar_mipi_dsi.h
> new file mode 100644
> index 000000000000..ff759fc5edc7
> --- /dev/null
> +++ b/drivers/gpu/drm/rcar-du/rcar_mipi_dsi.h
> @@ -0,0 +1,31 @@
> +/* SPDX-License-Identifier: GPL-2.0 */
> +/*
> + * R-Car DSI Encoder
> + *
> + * Copyright (C) 2022 Renesas Electronics Corporation
> + *
> + * Contact: Tomi Valkeinen <tomi.valkeinen at ideasonboard.com>
> + */
> +
> +#ifndef __RCAR_MIPI_DSI_H__
> +#define __RCAR_MIPI_DSI_H__
> +
> +struct drm_atomic_state;
> +struct drm_bridge;
> +
> +#if IS_ENABLED(CONFIG_DRM_RCAR_MIPI_DSI)
> +void rcar_mipi_dsi_pclk_enable(struct drm_bridge *bridge,
> + struct drm_atomic_state *state);
> +void rcar_mipi_dsi_pclk_disable(struct drm_bridge *bridge);
> +#else
> +static inline void rcar_mipi_dsi_pclk_enable(struct drm_bridge *bridge,
> + struct drm_atomic_state *state)
> +{
> +}
> +
> +void rcar_mipi_dsi_pclk_disable(struct drm_bridge *bridge)
> +{
> +}
> +#endif /* CONFIG_DRM_RCAR_MIPI_DSI */
> +
> +#endif /* __RCAR_MIPI_DSI_H__ */
--
Regards,
Laurent Pinchart
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